The present invention relates to a video display positioning system of the type in widespread use in passenger-aircraft entertainment systems and other systems such as may be found in ships, boats, trains, buses and other environments where a retractable video display is advantageous.
Video display screens, typically of the liquid-crystal type (LCD), are in widespread use in passenger-aircraft entertainment systems. These screens are usually mounted in the bottom of overhead luggage bins, or alternatively in the aircraft center-aisle ceiling or in seat-back trays. The screens are movable between a stowed or retracted position when the entertainment system is not in use, and a deployed or extended position to enable viewing by seated passengers.
Known electromechanical actuators for moving screens between stowed and deployed positions and the systems in which they are found are characterized by noisy operation, and poor reliability. These problems are an annoyance to passengers and a maintenance problem for operators of transport aircraft. These problems are essentially solved by the hydraulic screen-positioning system of the present invention.
The present invention relates to a video display positioning system in which a retractable video display is operated by use of a hydraulic-mechanical actuator and a control system which permits communication from a central control station to individual units.
Preferred embodiments of the present invention are directed to video screen positioning systems in which the operation of the screen from a retracted, unused position to an extended position for use in viewing the screen is accomplished by a hydraulic system which includes a hydraulic circuit and electric motor, a solenoid valve, a cylinder that encloses two, opposed open-ended pistons that are forced together to create linear motion in a first direction and a spring that functions as a restoring force to separate the two pistons and cause linear motion in a second, opposite direction, a linear-to-rotary motion linkage connected to the screen, and sensing and control circuitry for monitoring the position of system components pistons and to the screen and controlling operation of the system components.